PET/CT imaging can show precise areas of increased or decreased radiotracer uptake in the brain and physicians use this information for diagnosis of brain disease. Different radiotracers can show glucose metabolism, blood flow, oxygen and amyloid plaque in the tissues of the working brain.
Brain Metabolic Imaging with 18F FDG
Brain tumors, strokes, and neuron-damaging diseases which cause dementia such as Alzheimer's disease, all cause great changes in brain metabolism, which in turn causes easily detectable changes in PET scans.
In Alzheimer's disease, for example, there is a characteristic pattern of decreased biomarker uptake in the posterior parietotemporal cortex, which could be caused by neuronal depletion in that area. Physicians use this type of information to differentiate Alzheimer's disease from fronto-temporal and other dementia.
In a patient who experiences epileptic seizures, between seizures the PET scan displays decreased metabolism in the area of the seizure focus, but increased metabolism in that same area during a seizure. Physicians utilize this information to pinpoint the focus of a seizure prior to surgery.